diff --git a/help/faq.py b/help/faq.py index 8240f33762..4434647299 100755 --- a/help/faq.py +++ b/help/faq.py @@ -74,10 +74,8 @@ class faq_section: def print_contents(self): # Table header print((""" - - %s - -""" % (self.get_num_string(), self.get_header_level(), self.get_num_name(), self.get_header_level()))) + %s +""" % (self.get_header_level(), self.get_num_string(), self.get_num_name(), self.get_header_level()))) # Questions and Answers for qa in self.qa: @@ -87,12 +85,9 @@ class faq_section: tag = qa[3] print('

') - print(('Q %s:' % (id, id))) if tag is not None: - print(('' % tag)) - print(('%s' % (question))) - if tag is not None: - print('') + print(('' % (tag))) + print(('Q %s: %s' % (id, id, id, question))) print('

') print('

') @@ -216,9 +211,7 @@ def answer(text): # Create the index def create_index(): print(""" - -

Index

- +

Index

""") for sec in sections: sec.print_index() @@ -240,14 +233,11 @@ def create_output(header='', footer=''): def main(): header = '''\ - - - + + - Wireshark FAQ - + +Wireshark Frequently Asked Questions ''' @@ -277,24 +267,24 @@ and educators around the world use it regularly. It is freely available as open source, and is released under the GNU General Public License version 2. -
+
It is developed and maintained by a global team of protocol experts, and it is an example of a -disruptive +disruptive technology. -
+
Wireshark used to be known as Ethereal®. See the next question for details about the name change. If you're still using Ethereal, it -is strongly -recommended that you upgrade to Wireshark. +is strongly recommended that you upgrade to Wireshark as Ethereal is +unsupported and has known security vulnerabilities. -
+
For more information, please see the -About Wireshark +About Wireshark page. """) @@ -305,13 +295,13 @@ In May of 2006, Gerald Combs (the original author of Ethereal) went to work for CACE Technologies (best known for WinPcap). Unfortunately, he had to leave the Ethereal trademarks behind. -
+
This left the project in an awkward position. The only reasonable way to ensure the continued success of the project was to change the name. This is how Wireshark was born. -
+
Wireshark is almost (but not quite) a fork. Normally a "fork" of an open source project results in two names, web sites, development teams, support @@ -321,16 +311,17 @@ Wireshark. There has been no active development on Ethereal since the name change. Several parts of the Ethereal web site (such as the mailing lists, source code repository, and build farm) have gone offline. -
+
More information on the name change can be found here: - +

+

""") @@ -342,7 +333,7 @@ wireshark-users mailing list. Subscription information and archives for all of Wireshark's mailing lists can be found at %s. An IRC channel dedicated to Wireshark can be found at %s. -
+
Self-paced and instructor-led training is available at Wireshark University. @@ -366,7 +357,7 @@ Wireshark is pronounced as the word wire followed immediately by the word shark. Exact pronunciation and emphasis may vary depending on your locale (e.g. Arkansas). -
+
It's spelled with a capital W, followed by a lower-case ireshark. It is not a CamelCase word, i.e., WireShark @@ -381,12 +372,12 @@ license fee. The version of Wireshark you download isn't a "demo" version, with limitations not present in a "full" version; it is the full version. -
+
The license under which Wireshark is issued is the GNU General Public +href="https://www.gnu.org/licenses/gpl-2.0.html">the GNU General Public License version 2. See the GNU +href="https://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.html">the GNU GPL FAQ for some more information. """) @@ -396,11 +387,11 @@ That depends. Did they provide any sort of value-added product or service, such as installation support, installation media, training, trace file analysis, or funky-colored shark-themed socks? Probably not. -
+
-Wireshark is available for anyone to download, -absolutely free, at any time. Paying for a copy implies that you should -get something for your money. +Wireshark is available for +anyone to download, absolutely free, at any time. Paying for a copy implies +that you should get something for your money. """) question("Can I use Wireshark commercially?") @@ -409,7 +400,7 @@ Yes, if, for example, you mean "I work for a commercial organization; can I use Wireshark to capture and analyze network traffic in our company's networks or in our customer's networks?" -
+
If you mean "Can I use Wireshark as part of my commercial product?", see the next entry in the FAQ. @@ -421,7 +412,7 @@ question("Can I use Wireshark as part of my commercial product?", answer(""" As noted, Wireshark is licensed under the GNU General Public +href="https://www.gnu.org/licenses/gpl-2.0.html">the GNU General Public License, version 2. The GPL imposes conditions on your use of GPL'ed code in your own products; you cannot, for example, make a "derived work" from Wireshark, by making modifications to it, and then sell the @@ -429,23 +420,23 @@ resulting derived work and not allow recipients to give away the resulting work. You must also make the changes you've made to the Wireshark source available to all recipients of your modified version; those changes must also be licensed under the terms of the GPL. See the -GPL +GPL FAQ for more details; in particular, note the answer to the +href="https://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.html#GPLCommercially">the question about modifying a GPLed program and selling it commercially, and the +href="https://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.html#LinkingWithGPL">the question about linking GPLed code with other code to make a proprietary program. -
+
You can combine a GPLed program such as Wireshark and a commercial program as long as they communicate "at arm's length", as per this +href="https://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.html#GPLInProprietarySystem">this item in the GPL FAQ. -
+
We recommend keeping Wireshark and your product completely separate, communicating over sockets or pipes. If you're loading any part of @@ -456,7 +447,9 @@ question("What protocols are currently supported?") answer(""" There are currently hundreds of supported protocols and media. Details can be found in the -wireshark(1) man page. +wireshark(1) +man page. """) @@ -476,14 +469,14 @@ Support for particular capture file formats is added to Wireshark as a result of people contributing that support; no formal plans for adding support for particular capture file formats in particular future releases exist. -
+
If a network analyzer writes out files in a format already supported by Wireshark (e.g., in libpcap format), Wireshark may already be able to read them, unless the analyzer has added its own proprietary extensions to that format. -
+
If a network analyzer writes out files in its own format, or has added proprietary extensions to another format, in order to make Wireshark read @@ -496,7 +489,7 @@ capture file (showing packet time stamps, packet lengths, and the top-level packet header) in order to reverse-engineer the file format. -
+
Note that there is no guarantee that we will be able to reverse-engineer a capture file format. @@ -512,7 +505,7 @@ do so), ATM connections (if the OS on which it's running allows Wireshark to do so), and the "any" device supported on Linux by recent versions of libpcap. -
+
See the list of supported capture media on various OSes for details (several items @@ -522,10 +515,11 @@ expect that it will be able to capture on many of them, but we haven't tried it ourselves - if you try one of those types and it works, please update the wiki page accordingly. -
+
It can also read a variety of capture file formats, including: +

+

so that it can read traces from various network types, as captured by other applications or equipment, even if it cannot itself capture on those network types. @@ -607,7 +602,7 @@ is run. To install pcap.h and bpf.h, you must run "make install-incl". If you're running Debian or Redhat, make sure you have the "libpcap-dev" or "libpcap-devel" packages installed. -
+
It's also possible that pcap.h and bpf.h have been installed in a strange location. If this is the case, you may have to tweak aclocal.m4. @@ -617,8 +612,8 @@ location. If this is the case, you may have to tweak aclocal.m4. question(""" Why do I get the error -

dftest_DEPENDENCIES was already defined in condition TRUE, -which implies condition HAVE_PLUGINS_TRUE
+dftest_DEPENDENCIES was already defined in condition TRUE, +which implies condition HAVE_PLUGINS_TRUE when I try to build Wireshark from SVN or a SVN snapshot? """) @@ -642,7 +637,7 @@ handling very long lines. On Solaris, for example, libtool to work; /usr/xpg4/bin/sed can handle it, as can GNU sed if you have it installed. -
+
On Solaris, changing your command search path to search /usr/xpg4/bin before /usr/bin should make the problem @@ -688,7 +683,7 @@ developer's packet use winsock.h. (2.3 uses would not be able to build with current versions of the WinPcap developer's pack.) -
+
Note that the installed version of the developer's pack should be the same version as the version of WinPcap you have installed. @@ -715,7 +710,7 @@ source, as well. (If you get the 1.2.10 versions from www.sunfreeware.org, and the problem persists, un-install them and try installing one of the other versions mentioned.) -
+
Similar problems may exist with older versions of GTK+ for earlier versions of Solaris. @@ -743,7 +738,7 @@ When an application is installed on OS X, prior to 10.4, it is usually "prebound" to speed up launching the application. (That's what the "Optimizing" phase of installation is.) -
+
Fink normally performs prebinding automatically when you install a package. However, in some rare cases, for whatever reason the prebinding @@ -752,13 +747,15 @@ actually becomes much slower, because the system tries in vain to perform prebinding "on the fly" as you launch the application. This fails, causing sometimes huge delays. -
+
To fix the prebinding caches, run the command +

 	sudo /sw/var/lib/fink/prebound/update-package-prebinding.pl -f
+

""") ################################################################# @@ -773,6 +770,7 @@ does my machine crash or reset itself? answer(""" This is almost certainly a problem with one or more of: +

+

so: +

+

""") question(""" @@ -822,12 +823,12 @@ into an Ethernet or Token Ring switch; on a switched network, unicast traffic between two ports will not necessarily appear on other ports - only broadcast and multicast traffic will be sent to all ports. -
+
Note that even if your machine is plugged into a hub, the "hub" may be a switched hub, in which case you're still on a switched network. -
+
Note also that on the Linksys Web site, they say that their auto-sensing hubs "broadcast the 10Mb packets to the port that operate @@ -837,7 +838,7 @@ you will not see traffic coming sent to a 100Mb port, and vice versa. This problem has also been reported for Netgear dual-speed hubs, and may exist for other "auto-sensing" or "dual-speed" hubs. -
+
Some switches have the ability to replicate all traffic on all ports to a single port so that you can plug your analyzer into that single port to @@ -849,7 +850,7 @@ Wiki for information on some switches. (Note that it's a Wiki, so you can update or fix that information, or add additional information on those switches or information on new switches, yourself.) -
+
Note also that many firewall/NAT boxes have a switch built into them; this includes many of the "cable/DSL router" boxes. If you have a box @@ -862,7 +863,7 @@ the modem, and the machine on which you're running Wireshark into a hub (make sure it's not a switching hub, and that, if it's a dual-speed hub, all three of those ports are running at the same speed. -
+
If your machine is not plugged into a switched network or a dual-speed hub, or it is plugged into a switched network but the port is @@ -870,6 +871,7 @@ set up to have all traffic replicated to it, the problem might be that the network interface on which you're capturing doesn't support "promiscuous" mode, or because your OS can't put the interface into promiscuous mode. Normally, network interfaces supply to the host only: +

+

Most network interfaces can also be put in "promiscuous" mode, in which they supply to the host all network packets they see. Wireshark will try to put the interface on which it's capturing into promiscuous mode @@ -888,14 +891,14 @@ interface on which it's capturing into promiscuous mode unless the don't support promiscuous mode, and some OSes might not allow interfaces to be put into promiscuous mode. -
+
If the interface is not running in promiscuous mode, it won't see any traffic that isn't intended to be seen by your machine. It will see broadcast packets, and multicast packets sent to a multicast MAC address the interface is set up to receive. -
+
You should ask the vendor of your network interface whether it supports promiscuous mode. If it does, you should ask whoever supplied the @@ -903,7 +906,7 @@ driver for the interface (the vendor, or the supplier of the OS you're running on your machine) whether it supports promiscuous mode with that network interface. -
+
In the case of token ring interfaces, the drivers for some of them, on Windows, may require you to enable promiscuous mode in order to capture @@ -911,7 +914,7 @@ in promiscuous mode. See the Wireshark Wiki item on Token Ring capturing for details. -
+
In the case of wireless LAN interfaces, it appears that, when those interfaces are promiscuously sniffing, they're running in a @@ -938,7 +941,7 @@ promiscuous mode will receive only unicast traffic sent to the MAC address for that interface, broadcast traffic, and multicast traffic sent to a multicast MAC address the interface is set up to receive. -
+
TCP doesn't use broadcast or multicast, so you will only see your own TCP traffic, but UDP services may use broadcast or multicast so you'll @@ -946,7 +949,7 @@ see some UDP traffic - however, this is not a problem with TCP traffic, it's a problem with unicast traffic, as you also won't see all UDP traffic between other machines. -
+
I.e., this is probably the same question as this earlier one; see the response to that question. @@ -961,7 +964,7 @@ that's not sending traffic to the switch and not being sent any traffic from other machines on the switch. ARP packets are often broadcast packets, which are sent to all switch ports. -
+
I.e., this is probably the same question as this earlier one; see the response to that question. @@ -977,14 +980,14 @@ network, or is there any broadcast traffic on the network or multicast traffic to a multicast group to which the machine running Wireshark belongs? -
+
If not, this may just be a problem with promiscuous sniffing, either due to running on a switched network or a dual-speed hub, or due to problems with the interface not supporting promiscuous mode; see the response to this earlier question. -
+
Otherwise, on Windows, see the response to this question and, on a UNIX-flavored OS, see the response to +
On Linux and FreeBSD, libpcap 0.8 and later support the API for Endace Measurement Systems' @@ -1014,7 +1017,7 @@ version of Wireshark and a shared libpcap library with DAG support, in order to do so with Wireshark. You should ask Endace whether that could be used to capture traffic on, for example, your T1/E1 link. -
+
See the SS7 capture setup page on the Wireshark @@ -1027,9 +1030,10 @@ question("""How do I put an interface into promiscuous mode?""") answer(""" By not disabling promiscuous mode when running Wireshark or TShark. -
+
Note, however, that: +

+

I.e., this is probably the same question as this earlier one; see the response to that question. """) @@ -1057,23 +1062,24 @@ I can set a display filter just fine; why don't capture filters work? answer(""" Capture filters currently use a different syntax than display filters. Here's the corresponding section from the -wireshark(1) - man page: +wireshark(1) +man page: -
+
"Display filters in Wireshark are very powerful; more fields are filterable in Wireshark than in other protocol analyzers, and the syntax you can use to create your filters is richer. As Wireshark progresses, expect more and more protocol fields to be allowed in display filters. -
+
Packet capturing is performed with the pcap library. The capture filter syntax follows the rules of the pcap library. This syntax is different from the display filter syntax." -
+
The capture filter syntax used by libpcap can be found in the tcpdump(8) @@ -1089,7 +1095,7 @@ There is a bug in some versions of libpcap/WinPcap that cause it to report parse errors even for valid expressions if a previous filter expression was invalid and got a parse error. -
+
Try exiting and restarting Wireshark; if you are using a version of libpcap/WinPcap with this bug, this will "erase" its memory of the @@ -1097,18 +1103,18 @@ previous parse error. If the capture filter that got the "parse error" now works, the earlier error with that filter was probably due to this bug. -
+
The bug was fixed in libpcap 0.6; 0.4[.x] and 0.5[.x] versions of libpcap have this bug, but 0.6[.x] and later versions don't. -
+
Versions of WinPcap prior to 2.3 are based on pre-0.6 versions of libpcap, and have this bug; WinPcap 2.3 is based on libpcap 0.6.2, and doesn't have this bug. -
+
If you are running Wireshark on a UNIX-flavored platform, run "wireshark -v", or select "About Wireshark..." from the "Help" menu in Wireshark, to @@ -1118,7 +1124,7 @@ or will need to build and install a later version of libpcap from the tcpdump.org Web site and then recompile Wireshark from source with that later version of libpcap. -
+
If you are running Wireshark on Windows with a pre-2.3 version of WinPcap, you will need to un-install WinPcap and then download and @@ -1137,7 +1143,7 @@ packets that the OS's raw packet capture mechanism (or the WinPcap driver, and the underlying OS networking code and network interface drivers, on Windows) will allow it to capture. -
+
Unless the OS always supplies packets with errors such as invalid CRCs to the raw packet capture mechanism, or can be configured to do so, @@ -1149,7 +1155,7 @@ necessary and possible, and make whatever changes to libpcap and the packet capture program you're using are necessary, if any, to support capturing those packets. -
+
Most OSes probably do not support capturing packets with invalid CRCs on Ethernet, and probably do not support it on most @@ -1158,7 +1164,7 @@ as some Ethernet drivers on FreeBSD; in those OSes, you might always get those packets, or you might only get them if you capture in promiscuous mode (you'd have to determine which is the case). -
+
Note that libpcap does not currently supply to programs that use it an indication of whether the packet's CRC was invalid (because the drivers @@ -1181,7 +1187,7 @@ the data that the OS's raw packet capture mechanism (or the WinPcap driver, and the underlying OS networking code and network interface drivers, on Windows) will allow it to capture. -
+
For any particular link-layer network type, unless the OS supplies the FCS of a frame as part of the frame, or can be configured to do so, @@ -1192,7 +1198,7 @@ configure it if necessary and possible, and make whatever changes to libpcap and the packet capture program you're using are necessary, if any, to support capturing the FCS of a frame. -
+
Most OSes do not support capturing the FCS of a frame on Ethernet, and probably do not support it on most other link-layer @@ -1202,7 +1208,7 @@ Ethernet interface in Mac OS X; in those OSes, you might always get the FCS, or you might only get the FCS if you capture in promiscuous mode (you'd have to determine which is the case). -
+
Versions of Wireshark prior to 0.9.15 will not treat an Ethernet FCS in a captured packet as an FCS. 0.9.15 and later will attempt to determine @@ -1225,7 +1231,7 @@ constructs an Ethernet header, and passes that packet to an internal network device object for the VLAN, which then passes the packets onto various higher-level protocol implementations. -
+
In order to see the raw Ethernet packets, rather than "de-VLANized" packets, you would have to capture not on the virtual interface for the @@ -1245,22 +1251,24 @@ IP address in the capture to convert it to a name (so that, for example, it can display the name in the source address or destination address columns), and that lookup process is taking a very long time. -
+
Wireshark calls a routine in the OS of the machine on which it's running to convert of IP addresses to the corresponding names. That routine probably does one or more of: +

+

If a DNS server that's used in an address lookup is not responding, the lookup will fail, but will only fail after a timeout while the system routine waits for a reply. -
+
In addition, on Windows systems, if the DNS lookup of the address fails, either because the server isn't responding or because there are no @@ -1273,7 +1281,7 @@ non-Windows machines wouldn't be running that software - the lookup will only fail after a timeout. Those timeouts can cause the lookup to take a long time. -
+
If you disable network address-to-name translation - for example, by turning off the "Enable network name resolution" option in the "Capture @@ -1286,7 +1294,7 @@ options in the preferences disalog box, and using the "Save" button in that dialog box; note that this will save all your current preference settings. -
+
If Wireshark hangs when reading a capture even with network name resolution turned off, there might, for example, be a bug in one of @@ -1298,7 +1306,7 @@ occurs in the most recent release of Wireshark, the bug should be reported to the Wireshark developers' mailing list at wireshark-dev@wireshark.org. -
+
On UNIX-flavored OSes, please try to force Wireshark to dump core, by sending it a SIGABRT signal (usually signal 6) with the @@ -1307,6 +1315,7 @@ installed. A stack trace can be obtained by using your debugger (gdb in this example), the Wireshark binary, and the resulting core file. Here's an example of how to use the gdb command backtrace to do so. +

         $ gdb wireshark core
@@ -1316,10 +1325,11 @@ core file.  Here's an example of how to use the gdb command
         $
+

The core dump file may be named "wireshark.core" rather than "core" on some platforms (e.g., BSD systems). -
+
Also, if at all possible, please send a copy of the capture file that caused the problem. When capturing packets, Wireshark normally writes captured @@ -1331,7 +1341,7 @@ Windows XP and Server 2003, and \\Users\\your login name\\AppData\\Local\\Temp on the main system disk on Windows Vista and later, so the capture file will probably be there. If you are capturing on a single interface, it will have a name of the form, -wireshark_<fmt>_<iface>_YYYYmmddHHMMSS_XXXXXX, where +wireshark_<fmt>_<iface>_YYYYmmddHHMMSS_XXXXXX, where <fmt> is the capture file format (pcap or pcapng), and <iface> is the actual name of the interface you are capturing on; otherwise, if you are capturing on multiple interfaces, it will have a name of the form, @@ -1364,7 +1374,7 @@ program from an account with administrator privileges; once you have run such a program, you will not need administrator privileges to run any such programs until you reboot. -
+
If you are running on Windows Windows XP or Windows Server 2003 and have administrator privileges or a WinPcap-based program has @@ -1372,21 +1382,21 @@ been run with those privileges since the machine rebooted, this problem might clear up if you completely un-install WinPcap and then re-install it. -
+
If that doesn't work, then note that Wireshark relies on the WinPcap library, on the WinPcap device driver, and on the facilities that come with the OS on which it's running in order to do captures. -
+
Therefore, if the OS, the WinPcap library, or the WinPcap driver don't support capturing on a particular network interface device, Wireshark won't be able to capture on that device. -
+
-

  • WinPcap 2.3 has problems supporting PPP WAN interfaces on Windows NT +WinPcap 2.3 has problems supporting PPP WAN interfaces on Windows NT 4.0, Windows 2000, Windows XP, and Windows Server 2003, and, to avoid those problems, support for PPP WAN interfaces on those versions of Windows has been disabled in WinPcap 3.0. Regular dial-up lines, ISDN @@ -1395,7 +1405,7 @@ such as T1/E1 lines are all PPP interfaces, so those interfaces might not show up on the list of interfaces in the "Capture Options" dialog on those OSes. -
    +
    On Windows 2000, Windows XP, and Windows Server 2003, but not Windows NT 4.0 or Windows Vista Beta 1, you should @@ -1405,9 +1415,9 @@ release, you should un-install it and install the final 3.1 release.) See the Wireshark Wiki item on PPP capturing for details. -
    +
    -
  • WinPcap prior to 3.0 does not support multiprocessor machines (note +WinPcap prior to 3.0 does not support multiprocessor machines (note that machines with a single multi-threaded processor, such as Intel's new multi-threaded x86 processors, are multiprocessor machines as far as the OS and WinPcap are concerned), and recent 2.x versions of WinPcap @@ -1416,28 +1426,27 @@ multiprocessor machine, which means that they may not show any network interfaces. You will need to use WinPcap 3.0 to capture on a multiprocessor machine. - - -
    +
    If an interface doesn't show up in the list of interfaces in the "Interface:" field, and you know the name of the interface, try entering that name in the "Interface:" field and capturing on that device. -
    +
    If the attempt to capture on it succeeds, the interface is somehow not being reported by the mechanism Wireshark uses to get a list of interfaces. Try listing the interfaces with WinDump; see the WinDump Web site +href="https://www.windump.org/">the WinDump Web site for information on using WinDump. -
    +
    You would run WinDump with the -D flag; if it lists the interface, please report this to wireshark-dev@wireshark.org giving full details of the problem, including +

    +

    If WinDump does not list the interface, this is almost certainly a problem with one or more of: +

    -so first check the -WinPcap FAQ or -the Wiretapped.net mirror of that FAQ, to see if your problem is -mentioned there. If not, then see the WinPcap support page +

    +so first check the +WinPcap FAQ to see if your problem is mentioned there. If not, then see the WinPcap support page - check the "Submitting bugs" section. -
    +
    If you are having trouble capturing on a particular network interface, first try capturing on that device with WinDump; see the WinDump Web site +href="https://www.windump.org/">the WinDump Web site for information on using WinDump. -
    +
    If you can capture on the interface with WinDump, send mail to wireshark-users@wireshark.org giving full details of the problem, including +

    +

    If you cannot capture on the interface with WinDump, this is almost certainly a problem with one or more of: +

    -so first check the -WinPcap FAQ or -the Wiretapped.net mirror of that FAQ, to see if your problem is -mentioned there. If not, then see the WinPcap support page +

    +so first check the +WinPcap FAQ to see if your problem is mentioned there. If not, then see the WinPcap support page - check the "Submitting bugs" section. -
    +
    You may also want to ask the wireshark-users@wireshark.org @@ -1509,7 +1519,7 @@ href="mailto:winpcap-users@winpcap.org">winpcap-users@winpcap.org mailing lists to see if anybody happens to know about the problem and know a workaround or fix for the problem. (Note that you will have to subscribe to that list in order to be allowed to mail to it; see the WinPcap support +href="https://www.winpcap.org/contact.htm">the WinPcap support page for information on the mailing list.) In your mail, please give full details of the problem, as described above, and also indicate that the problem occurs with WinDump, not just with Wireshark. @@ -1539,7 +1549,7 @@ on Windows NT 4.0, Windows 2000, Windows XP, and Windows Server 2003, and, to avoid those problems, support for PPP WAN interfaces on those versions of Windows has been disabled in WinPcap 3.0. -
    +
    On Windows 2000, Windows XP, and Windows Server 2003, but not Windows NT 4.0 or Windows Vista Beta 1, you should @@ -1567,7 +1577,7 @@ receiving packets. You can disable promiscuous mode using the dialog box, but this may mean that outgoing packets, or incoming packets, won't be seen in the capture. -
    +
    On Windows 2000, Windows XP, and Windows Server 2003, but not Windows NT 4.0 or Windows Vista Beta 1, you should @@ -1591,7 +1601,7 @@ Wireshark (or any other application using WinPcap) see outgoing packets; unfortunately, neither we nor the WinPcap developers know any way to make WinPcap and the VPN software work well together. -
    +
    Also, some drivers for Windows (especially some wireless network interface drivers) apparently do not, when running in promiscuous mode, @@ -1626,10 +1636,10 @@ your machine, not third-party traffic, and it'll look like Ethernet traffic and won't include any management or control frames, but that's a limitation of the card drivers. -
    +
    -See MicroLogix's +See the archived MicroLogix's list of cards supported with WinPcap for information on support of various adapters and drivers with WinPcap. """) @@ -1685,7 +1695,7 @@ Wireshark Wiki item on capture privileges for details on how to give a particular account or account group capture privileges on platforms where that can be done. -
    +
    If you are running Wireshark from an account with sufficient privileges, then note that Wireshark relies on the libpcap library, and on the @@ -1694,7 +1704,7 @@ captures. On some OSes, those facilities aren't present by default; see the Wireshark Wiki item on adding capture support for details. -
    +
    And, even if you're running with an account that has sufficient privileges to capture, and capture support is present in your OS, if the @@ -1702,25 +1712,26 @@ OS or the libpcap library don't support capturing on a particular network interface device or particular types of devices, Wireshark won't be able to capture on that device. -
    +
    On Solaris, note that libpcap 0.6.2 and earlier didn't support Token Ring interfaces; the current version, 0.7.2, does support Token Ring, and the current version of Wireshark works with libpcap 0.7.2 and later. -
    +
    If an interface doesn't show up in the list of interfaces in the "Interface:" field, and you know the name of the interface, try entering that name in the "Interface:" field and capturing on that device. -
    +
    If the attempt to capture on it succeeds, the interface is somehow not being reported by the mechanism Wireshark uses to get a list of interfaces; please report this to wireshark-dev@wireshark.org giving full details of the problem, including +

    +

    If you are having trouble capturing on a particular network interface, and you've made sure that (on platforms that require it) you've arranged that packet capture support is present, as per the above, first try capturing on that device with tcpdump. -
    +
    If you can capture on the interface with tcpdump, send mail to wireshark-users@wireshark.org giving full details of the problem, including +

    +

    If you cannot capture on the interface with tcpdump, this is almost certainly a problem with one or more of: +

    +

    so you should report the problem to the company or organization that produces the OS (in the case of a Linux distribution, report the problem to whoever produces the distribution). -
    +
    You may also want to ask the wireshark-users@wireshark.org @@ -1794,7 +1810,7 @@ libpcap/WinPcap get them from the OS kernel, so Wireshark - and any other program using libpcap, such as tcpdump - is at the mercy of the time stamping code in the OS for time stamps. -
    +
    At least on x86-based machines, Linux can get high-resolution time stamps on newer processors with the Time Stamp Counter (TSC) register; @@ -1807,7 +1823,7 @@ The Linux kernel must be configured with the CONFIG_X86_TSC option enabled in order to use the TSC. Make sure this option is enabled in your kernel. -
    +
    In addition, some Linux distributions may have bugs in their versions of the kernel that cause packets not to be given high-resolution time @@ -1831,7 +1847,7 @@ answer(""" That depends on the operating system on which you're running, and on the 802.11 interface on which you're capturing. -
    +
    This would probably require that you capture in promiscuous mode or in the mode called "monitor mode" or "RFMON mode". On some platforms, or @@ -1840,7 +1856,7 @@ promiscuous mode might not be sufficient. If you want to capture traffic on networks other than the one with which you're associated, you will have to capture in monitor mode. -
    +
    Not all operating systems support capturing non-data packets and, even on operating systems that do support it, not all drivers, and thus not @@ -1848,7 +1864,7 @@ all interfaces, support it. Even on those that do, monitor mode might not be supported by the operating system or by the drivers for all interfaces. -
    +
    NOTE: an interface running in monitor mode will, on most if not all platforms, not be able to act as a regular network @@ -1856,7 +1872,7 @@ interface; putting it into monitor mode will, in effect, take your machine off of whatever network it's on as long as the interface is in monitor mode, allowing it only to passively capture packets. -
    +
    This means that you should disable name resolution when capturing in monitor mode; otherwise, when Wireshark (or TShark, or tcpdump) tries @@ -1864,7 +1880,7 @@ to display IP addresses as host names, it will probably block for a long time trying to resolve the name because it will not be able to communicate with any DNS or NIS servers. -
    +
    See the Wireshark @@ -1901,16 +1917,18 @@ are directly handed to the capture interface by the OS, which means that they are handed to the capture interface without a TCP checksum being added to them. -
    +
    The only way to prevent this from happening would be to disable TCP checksum offloading, but +

    1. that might not even be possible on some OSes;
    2. that could reduce networking performance significantly.
    +

    However, you can disable the check that Wireshark does of the TCP checksum, so that it won't report any packets as having TCP checksum errors, and so that it won't refuse to do TCP reassembly due to a packet @@ -1922,7 +1940,7 @@ validity of the TCP checksum when possible" option, clicking "Save" if you want to save that setting in your preference file, and clicking "OK". -
    +
    It can also be set on the Wireshark or TShark command line with a -o tcp.check_checksum:false command-line flag, or manually set @@ -1947,6 +1965,7 @@ only as UDP.""") answer(""" Wireshark can identify a UDP datagram as containing a packet of a particular protocol running atop UDP only if +

    1. The protocol in question has a particular standard port @@ -1963,17 +1982,18 @@ for example, UDP traffic between two particular addresses and ports will be RTP traffic.
    +

    RTP doesn't have a standard port number, so 1) doesn't work; it doesn't, as far as I know, have any "signature", so 2) doesn't work. -
    +
    That leaves 3). If there's RTSP traffic that sets up an RTP session, then, at least in some cases, the RTSP dissector will set things up so that subsequent RTP traffic will be identified. Currently, that's the only place we do that; there may be other places. -
    +
    However, there will always be places where Wireshark is simply incapable of deducing that a given UDP flow is RTP; a mechanism @@ -2011,7 +2031,7 @@ answer(""" You cannot use the name of a saved display filter as a filter. To filter the display, you can enter a display filter expression - not the name of a saved display filter - in the -"Filter:" box at the bottom of the display, and type the key or +"Filter:" box at the bottom of the display, and type the <Enter> key or press the "Apply" button (that does not require you to have a saved filter), or, if you want to use a saved filter, you can press the "Filter:" button, select the filter in the dialog box that pops up, and @@ -2028,7 +2048,7 @@ would be hard to implement in capture filters without changes to the capture filter code, which, on many platforms, is in the OS kernel and, on other platforms, is in the libpcap library. -
    +
    After capture, you can search for text by selecting Edit→Find Packet... and making sure String is selected. Alternately, you can @@ -2047,19 +2067,13 @@ href="https://wiki.wireshark.org/CaptureFilters">CaptureFilters     page on the Wireshark Wiki to see if anybody's added such a filter. -
    +
    Note that Wireshark was not designed to be an intrusion detection system; you might be able to use it as an IDS, but in most cases software -designed to be an IDS, such as Snort -or Prelude, will probably work +designed to be an IDS, such as Snort +or Prelude, will probably work better. - -
    - -The Bleeding Edge of Snort -has a collection of signatures for Snort to detect various viruses, -worms, and the like. """) #################################################################